Locomotive piston valve



Filed Feb. 21, 1941 2 Sheets-Sheet l 28 FIG.

SWW/who@ JOHN T. SNOREN mf a .In il H IH x a rum w 3 32. m. .r 1.1: rL/ j oooodomvfe e l, ,f @mai f2 L... c, runmlf;

SePt- 12, 1944 J. T. sNoREN 2,358,036

LOCOMOTIVE PISTON VALVE Filed Feb. 2l, 1941 2 Sheets-Sheet 2 5o 42 FIG. 4.

`V JOHN* I A A FIG. Il.

Patented Sept. 12, 1.944

UNITED STATES PATENT `OFFICE LocoMoTIvE PIsToN VALVE John T. Snaren, St. AIlaul, Minn.

Application February 2-1, 1941, Serial No. 380,079

v (Cl. 309-26). i Y

2. Claims.

My invention relates to an improvement in locomotive piston valves. With the advent of ymodern streamlined locomotives operating at increasingly higher speeds than heretofore possible, the problem of efficiently controlling friction in the moving parts is of primary importance.

An object of my invention is to simplify the construction and atthe same time improve the operation `of locomotive piston valves. Modern locomotives operate with super-heated steam and pressures ranging in high temperatures. 'I'hus the problem of properly lubricating the working surfaces where enormous frictional drag is set up is particularly diflicult. In my form of construction, I have provided a lightweight piston Valve. by having a hollow cylindrical tubularportion and by making the end members hollow. By providing a lightweight valve construction, the operation of the valve is improved, and the frictional drag between the rings and the valve bushings is greatly reduced. By cutting down the friction of the piston valves, the life of the valve is greatly increased and at the same time is operated with much greater efficiency.

Locomotive piston valves at the present time are provided with packing `rings which form an enormous frictional drag against the walls of the valve bushings mainly by steam pressure getting under the rings, causing undue expansion of the rings. These old type valves are also heavy, which increases the wall drag. The modern locomotives operate under such high temperatures and such enormous pressures, that it is a problem to properly lubricate the working surfaces of the piston valve. Thus when the rings are eX- panded by the pressure back of the rings, there is greater friction between the rings and the valve bushings. Therefore if the friction is too great, the lubrication is reduced and the rings wear out faster, causing the piston valve to operate inefficiently.

Too much'friction between the rings and the cylinder walls of the valve causes the cylinder walls to run dry. Thus by the cylinder walls running dry, the valve motion itself often breaks down or makes it necessary to make repairs.

It is a feature of my invention to provide a piston valve which will eliminate the undesirable features of .the present type of valve. My lightweight valve will give free operation, practically eliminate lubrication troubles, and will overcome muchA of the friction now present inthe old' valves, thereby reducingthe danger of some parts of the valve motion tearing itself apart in service. c l

l expanding the steam rings as the steam pressure The valve construction is made lighter against the sealing ring forces it laterally against the steam rings. The angular face of the con-'- tinuous sealing ring acts yagainst the'l similar angular face of the adjacent cut steam ring and the latter will be forced to expand moderately'by the reciprocation of the valve. "It is another feature of'my invention to provide an expansion control ring which moves horilzontally by the action of steam when the piston valve is in motion. The expansion controllring is provided with springs which act against the control rin-g to keep it in proper working' loca-v tion when the locomotive piston valve is idle. The expansion control ring forces the exhaust ring on the locomotive' piston valve to eliminate the expansive force of steam expanding itselfunder the ring against the walls of the valve. vIn the case of the exhaust ring, the force of the control ring against the exhaust ringcuts'downjor reduces the inside area 4of the 4exhaust ring. This is done by introducing a triangular ring., This ring is made in one piece and therefore cannot expand. By keeping the two rings, the exhaust ring and control ring, in contact, the force of the exhaust ring against the bushing Vsurface will greatly reduce the friction.

Thus as has been lstated before, the raction of the sealing rings is mainly to shut off steam fronti getting beneath the steam rings and causingwthe steam rings to overexpand, causing A'undue friction between the steam rings and the cylinder wall in the valve. When the friction of the rings against the valve bushings has been cutdownby the use of my sealing rings, lubricating the moving parts can be accomplishedvery easily. Therefore, the life of my locomotive pistonvalve is greatly increased over old types, andthe Working eniciency of the piston valve is greatly increased.

These and other objects and novel features of my invention will be more clearlyA andlfullyfset forth in the following'specication.and claims.

In the drawings forming apart of my .speci-,5 cation:

horizontally against the sealing ring 25.

' steam ring.

Figure 8 is a cross-sectional view showing a similar steam ring to that shown in Figure 7.

, Figure 9 is a sectional view through the piston valve exhaust ring arrangement.

Figure 10 is a sectional view through an expansionrcontrol-ring.. Y Y

Figure 11 is a View showing the exhaust ring Where it is cut.

My invention comprises a locomotive piston valve A which is best shown'in Figure 2 of the drawings. The locomotive hollow spoolfshaped piston valve A is composed of a hollow cylindrical section I0, follower plates a stem I2, steam rings I3, an exhaust ring I4, bull rings YI5, and tightening screws I6. The section Il) .comes in contact in grooves |'I with the valve :body 2|. The steam rings I3'and |9 are grooved Vat I8, which causes the steam rings I3 and I9 to interlock with one-another. The steam ring I9 is grooved at 20 and interlocks with the bull ring I5. The exhaust ring I4 is also grooved at 22 and is made to interlock also with the bull ring I5. Follower plates are screwed in place by screws I6 to the body 2 I. Thus by tightening the screws I6, the follower plate causes the exhaust ring, the bull ring, and steam rings to tighten in place.

The stem I2 is anged at 23 in a shoulder manner, andthe shoulder rests against the body of the valve 2|.

the threaded end of the stem I2 and tightens against the body 2| of the piston valve.

At one end of the piston valve, VI provide a nut 24. The nut 24 is screwed on Thus by tightening the nut 24 to the stern I2, the fbody of the pistonV valve is pulledv against the section I0, making the unit compact.

. I provide a sealing ring 25 which is placed next to the steam ring I3. The sealing ring 25 is made in one solid piece having no cut or joints. An open steam port 26 is provided around the lbody of the piston valve. When the steam enters the open steam port 26, it acts vertically and The sealing ring 25 then is forced downwardly and motive piston valve as it would be when it is in operation. The drawing in Figure 1 shows a cylinder 21 and a Vpiston 28 connected to a piston rod 29 in operation. The locomotive piston valve Ais located above the steam cylinder 2l, and when the locomotive is in operation, the piston valve A opens and closes steam ports which allow the steam to enter and escape from the steam cylinder 21 where the piston and piston rod are operated. 'Ihe steam enters the steam port 30 and goes into a chamber 3|. When the piston valve is to the extreme right, the steam enters the steam port 32. The steam then follows the steam passage 33 into the cylinder 21. The steam acts against the face of the piston 34, causing the piston and piston rod to move outwardly, forcing the steam which is in the other side of the chamber to go out the steam passageV 35, up out through anv exhaust 36. When the locomotive piston valve is to the eXtreme-left, the steam enters the steam passage 3,5 which leads into the cylinder 21,causing the piston 34 to go in the oppositedirection. As the piston 34 moves in the opposite direction, the steam which is between the piston' and the cylinder` wall is forced up out through the steam-'passage 33, out through an exhaust port V31. Thus as can be seen in the drawings, the locomotive piston valve operates the entry and exhaust steam ports. f

The locomotive valve piston rings ride on valve bushings 39. Therefore it is very necessary that the Valve bushings 39 are properly lubricated so that' wear and friction between the valve rings and the valve bushings is as little as possible. As stated above, when stea'm nds its way underneath the piston valve rings, the rings are caused to overexpand, greatly increasing the friction vbetween the rings andthe valve bushing. Therefore it is an object of my invention toreduce the frictionlbetween the rings and the valve bushings 39.V By using the sealing ring 25 to cut off the steam from entering beneath the steam rings of the piston valve, the rings cannot overex-v pand, and therefore friction is greatly reduced.

In the cases kwhere there isV great friction between the rings and the valve wall, it is difficult to lubricate the valve walls in the proper way inasmuch as the rings scrape the valve wall of the bushings dry. When the valve wall of the bushings becomes dry, friction is increased, which often leads to the break-'down of the piston out of operation altogether.

outwardly causing .the steam rings I3 and I9 toV press against each other, locking them more securely. With the use of the sealing ringV 25,

steam which enters the steam port 26 cannot work its Vway beneath the steam rings. Previously,V when steamiound its way beneath the steam rings of a locomotive piston valve, the

' pressure of the steam caused undue expansion of the steam rings, `causing them to come in contact with the valve bushing walls, thus causing great friction. lBy the use vof the sealing ring 25 as illustrated in Figure 2, the steam is, completely shut Q from entering underneath the steam rings. Thus the steam rings cannot overexpand, causing great friction between the rings andgthe valve bushing.

In Figure 1 of the drawings, I show my loco- I 8 of the drawings.

As shown in Figure Grof the drawings, the sealing ring 25 is shown having a thin skirt 4I)v upon which the steam force acts vertically tending to close the sealing ring up tight against the 'body 2| of the locomotive piston valve. In Figure 7 of the drawings, the steam ring I3 is shown in cross-section through the sealing key 4| indicated loy the line 'I--l of Figure 5. The steam rings I3 and I9 are sealed bythe use of sealing keys which help to prevent the steam from getting under the steam rings. The steam ring I9 is very similar to the steam ring I3 Vas shown in Figure Figure 9'of the drawings shows amodled form of my invention wherein atriangular expansion control ring acts similarly to'that of the sealing ring 25. An exhaust ring 42 -is grooved at 43 and when the exhaust ring 42 expands, it ls interlocked at 44 with a bull ring 45. -Springs 46 are Y provided at even intervals against the expansion Vcontrol ring. The springs 46 tend to hold thev expansion control ring 41 in proper position when the locomotive piston valve is idle. A follower plate 49 holds the springs 46 in place against the sealing ring 41. The expansion control ring 41 is not cut, and is made of one piece. The expansion control ring as stated above is triangular as shown in cross-section in Figure 10 of the drawings. A side 48 lies against the exhaust ring 42. The exhaust ring 42 is provided with a thin cut I50 through which steam enters and fills up the space 5| underneath the ring.

The steam causes the exhaust ring to expand and also passes through vents (cut in the corners) of one-piece control ring 41, causing it to press horizontally against the exhaust ring, which action wil1 greatly modify the outward force of the exhaust ring. The control ring, bein-g made in one piece, does not move outwardly, -but rather moves horizontally. It will also be apparent that my construction will prevent rings from wearing in the ring grooves and practically overcome slamming of the rings, because the control ring presses horizontally against the exhaust ring.

In the method just described, the expansion of the exhaust ring can be controlleda so that in this Way the friction between the exhaust ring and the valve bushings is greatly reduced.

In accordance with the patent statutes, I have described the principles of construction and operation of my locomotive piston valve; and while I have endeavored to set forth the best embodiments thereof, I desire to have it understood that this is only illustrative of a means of carrying out my invention, and that obvious changes can be made within the scope of the following claims without departing from the spirit of my invention.

I claim:

1. In combination with a piston having about it an annular groove with a cylindrical floor, a

sealing ring having a base engaging said cylin-A drical floor and formed with an outer wall curved in cross-section and an annular inner side wall in slanting relation outwardly to the other Wall of the groove, a steam rin-g iloatingly mounted in said groove having a correspondingly slanting side wall trending in the opposite direction and engaging theslopng side wall of the groove, said sloping walls holding the inner steam ring wall spaced .from the iioor of the groove, and means for admitting pressure steam against the transversely curved surface of the outside wall of the sealing ring7 whereby the pressure will hold said ring upon the floor of the groove and cause contact of the sloping wall of the Sealing ring and the sloping wall of the steam ring to tend to hold the steam ring in an outwardly operative position and to seal it against steam pressure.

2. In combination with a piston having about it an annular groove with a cylindrical floor, a

sealing ring having a base engaging said cylindrical floor and formed with an outer wall curved in cross-section and an annular inner side wall in slanting relation outwardly to the other wall of the groove, a steam ring floatingly mounted in said groove having a correspondingly slanting side wall trending'in the opposite direction and engaging the sloping side Wall of the groove, said sloping walls holding the inner steam ring wall spaced from the floor of the groove, means for admitting pressure steam against the transversely curved surface. of the outside Wall of the sealing ring, whereby the pressure will hold said ring upon the floor of the groove and cause contact of the sloping wall of the sealing ring and the sloping wall of the steam ring to tend to hold the steam ring in an outwardly operative position and to seal it against steam pressure, and means for locking said steam ring in the groove.

JOHN T. SNOREN. 

